Because of the high heat and low humidity in the summer in death valley, california, a visitor requires about one quart of water for every two miles traveled on foot. calculate the approximate number of liters required for a person to walk 15 kilometers in death valley. because of the high heat and low humidity in the summer in death valley, california, a visitor requires about one quart of water for every two miles traveled on foot. calculate the approximate number of liters required for a person to walk 15 kilometers in death valley. 46 l 70 l 18 l 4.4 l